设计了横向结构的半绝缘GaAs光导开关和SiC光导开关。在不同的直流偏置电压下,使用波长为1 064 nm的激光脉冲触发使开关导通,研究了非本征光电导方式下GaAs光导开关和SiC光导开关的光电导特性。实验中获得了GaAs光导开关的暗态伏安曲线和200～1 100 nm波长范围内吸收深度随波长的变化曲线,得到了大功率GaAs光导开关在线性模式和非线性模式下的电流波形,并进行了比较,讨论了非线性模式下大功率GaAs光导开关的奇特光电导现象。对非本征光电导方式下的SiC光导开关进行了初步实验研究,得到了偏置电压3.6 kV下开关的电压和电流波形。

In this paper semi-insulating GaAs photoconductive semiconductor switch(PCSS) and SiC PCSS were fabricated. Triggered by laser pulse at a wavelength of 1 064 nm,photoconductivity tests of the PCSSs were performed at different bias voltages. Dark current-voltage characteristics of GaAs PCSS and the absorption depth of GaAs with different wavelength were obtained experimentally. GaAs PCSSs both in linear mode and nonlinear mode were studied,and peculiar photoconductivity of high-power GaAs PCSS in nonlinear mode was discussed. High-power SiC PCSSs employing extrinsic photoconductivity are under development,and initial experimental results are presented in this paper.